Studies of the polarogrphic behavior of bovine serum albumin (BS) are being extended to a study of the structure of BSA adsorbed as a monomolecular film on drops of mercury. Apparently, the BSA is adsorbed in the unfolded form, and there is almost certain proof that in the adsorbed state its structure is the same as that of completely reduced protein (P(SH)35). Various modified forms of BSA are being prepared in which the -S-S- groups are partly or entirely changed into =SSO3, -SH, -(SH)35, -(SCH2COONa)35. Their immunological, carcinogenic, and polarographic properties and their structures will be studied. Cooperation of cancer research centra will be solicited in a further study of the polarographic cancer test in blood and, if possible, replaced by simpler chemical tests. Bibliographic references: Brdicka Currents Observed with Bovine Serum Albumin and Completely Reduced Bovine Serum Albumin in the Presence of Urea, "I.M. Kolthoff, K. Yamashita, and Tan Boen Hie, Proc. Nat. Acad. Sci. USA, 72:6, 2044-2048, 1975. "Effects of Tetraalkylammonium Salts on Brdicka and Presodium Currents of Bovine- Serum Albumin," I.M. Kolthoff and K. Yamashita, Proc. Nat. Acad. Sci. USA, 72:8, August 1975.